Liquid pressurization systems produce high pressure (e.g., up to 90,000 pounds per square inch or greater) streams of liquid for various applications. For example, high pressure liquid may be delivered to a liquid jet cutting head, a cleaning tool, a pressure vessel or an isostatic press. In the case of liquid jet cutting systems, liquid is forced through a small orifice at high velocity to concentrate a large amount of energy on a small area. To cut hard materials, a liquid jet can be “abrasive” or include abrasive particles for increasing cutting ability. As used herein, the term “liquid jet” includes any substantially pure water jet, liquid jet, and/or slurry jet. However, one of ordinary skill in the art would easily appreciate that the invention applies equally to other systems that use liquid pumps or similar technology.
To generate a high pressure liquid stream, a liquid pressurization system uses a high-pressure intensifier pump. A high-pressure intensifier pump uses a plunger to draw a volume of liquid into a cylinder on an intake stroke and pressurize the volume of liquid on a pressure stroke. As the plunger reciprocates within the cylinder, it passes through a seal assembly. The seal assembly prevents pressurized liquid in the cylinder from flowing past the plunger and leaking from the pump. Typically, a pump has multiple cylinders, and pressurized fluid from an outlet area of each cylinder is collected in an accumulator. High-pressure fluid collected in this manner is then provided to a tool to perform a desired function, e.g., cutting or cleaning.
While seal assemblies are critical to the proper functioning of the intensifier pump, current seal assemblies suffer from at least two significant drawbacks. First, current seal assemblies are bulkier than necessary. Added bulk can waste space in the pump and raise manufacturing costs. Second, current seal assemblies wear significantly with pump use and therefore require frequent replacement. What is needed is a seal assembly that is compact, robust, and easy to install—and that has a long service life and a low manufacturing cost.